The present invention relates to an improved magazine of the kind used for receiving a stack of film sheets enclosed in a flexible bag and wherein the bag is removed from the sheets to enable feeding seriatim of the sheets from the magazine.
U.S. Pat. No. 4,135,800, issued Jan. 23, 1979 relates to a cassette for a stack of single film sheets, such as x-ray film sheets. The cassette is opened, an envelope containing the film sheets is inserted into the cassette, and then the cassette is closed. As the cassette is closed, cutters or knives pierce the envelope and certain of the cutters also abut against the stack of sheets to approximately position the stack of sheets in the cassette. The envelope is then pulled away from the film and through a slot forming a lightlock. As the envelope is removed, the cutters shred the envelope in a lengthwise direction, and it's possible that pieces of the envelope may not be entirely removed and could interfere with feeding of film from they cassette.
It also is known from U.S. Pat. No. 3,934,150 issued Jan. 20, 1976, to provide a sheet feeding device which receives a bag containing sheets of film and a doubling plate that fits over the front shet, back sheet and upper edge of the stack of sheets. When the bag is in the device the bag is slit at its lower end and then the bag material and doubling plate are raised to uncover the lower portions of the sheets of film so that can be removed by suction cups. The vertical orientation required for removing of the package material relative to the sheets of film may be satisfactory for the apparatus shown in such patent, but is not generally applicable to other kinds of apparatus.
When a bag containing a stack of sheets is removed from the bag, there is a tendency for sheets in the stack to be moved with the bag material. This can cause displacement of the sheets from their desired position and result in a misfeed of sheets from the magazine.